Process of producing condensation products



Patented I Dec. 29, 1942 UNITED ,STATES PATENT OFFICE PROCESS OFPRODUCING CONDENSATION PRODUCTS Winfrid Hentrich, Dessau-Rosslau,Anhalt, and

Erik Schirm, Dessau in Anhalt, Germany, assignors, by mesne assignments,to "Unicliem Chemikalien Handels, A.-G., Zurich, Switlera land, acorporation of Switzerland No Drawing. Application March 25, 1939,Serial No. 264,126. In Germany March 25, 1938 10 Claims.

with at least one aromatic amino or one mercapto compound.

One of the principal objects of this invention is to provide industry,particularly the textile, leather and allied branches of industry, witha water-soluble organic treating agent. A special object of theinvention is to provide the leather industry with a valuable tanningagent which may be used alone or in combination. with other tanningagents.

Another object of the invention is to provide the textile industry withtreating agents which are valuable in dyeing operations. Yet anotherobject of the invention is to produce compounds which are useful in thepreparation of insecticides such as those used as protection againstmoths.

According to the present invention commercially valuable products areproduced by condensing heterocyclic compounds having at least twoC(halogen) =N groups with at least one aromatic compound amino ormercapto compound having present one or more acid amide groups, but freeof further groups capable of forming azo dyes. The amino or mercaptocondensing compound may be used in a quantity to replace all or lessthan all of the exchangeable halogen atoms present in the heterocyclicring, and if less is used it is usually desirable to condense theheterocyclic compound further with compounds containing RR'N--, R.S-, orR0?- groups, the R and R being hydrogen or a desired hydrocarbon group.The ultimate condensation products in any event must contain one or morewater-sclubilizing groups, and hence at least one of the groupsintroduced into the heterocyclic ring must contain one or more of suchgroups. The condensing compounds used for condensation with theheterocyclic compounds may contain the usual heteroatoms such ashalogen, oxygen, sulfur, and nitrogen, or heteroatomic groups containingsuch atoms.

In accordance with another procedure, the condensation products of theinstant invention may be obtained by condensing the halogen-containingheterocyclic compounds in separate steps with the compounds normallyobtainable by the splitting of the foregoing condensing compoundsinstead of with the compounds themselves which procedure is hereinaftermore fully disclosed.

The oondensations of the presentinvention take place under mildconditions when the reagents are dissolved in suitable solvents such asacetone and water. The reaction proceeds smoothly especially when suchacid-binding agents as sodium acetate, alkali metal or alkaline earthformates, oxides or hydroxides, carbonates, or pyridine, and the likeare present. The conversion takes place quantatively inmost instances,and the intermediate products as well as the ultimate prodnets arecapable of production by commercially feasible methods.

In a preferred embodiment f the invention, l,3,5 -triazines, such ascyanuric halogenides, constitute the heterocyclic raw materials in thecondensation process. Other halogen substituted compounds, however, suchas those of the diazines, including such compounds as pyrimidine,pyrazine, quinazoline, quinoxaline, phthalazine and the like, also arevaluable as raw materials.

The condensation processes of the invention are not limited to compoundshaving only one heterocyclic ring, for compounds having more than one ofsuch rings likewise comprise suitable raw materials. These multiringedcompounds may be built up by coupling or bridging together two or moreheterocyclic rings through atoms or atomic groups, such as by usingcyclic or acyclic diamines. For instance, such compounds can be producedby condensing one mole of a diamine, such as ethylene diamine, phenylenediamine, and the like, with two moles of the heterocyclic compound, suchas cyanuric chloride. In this proc-- ess of condensation, theheterocyclic rings may be partially substituted before the condensationwith the previously referred to amino or mercapto compounds containingthe acid amide groups,

Furthermore, the diamines may themselves contain acid'amide groups. Forinstance, sucha compound as N-(3',5'-diamino benzene sulfonyl)sulfanilic acid may be used as the atomic bridge A wire variety ofaromatic amino or mcrcapto contain water-solubilizing groups such asacid radicals of organic and inorganicpolybasic acids, quaternaryammonium groups, polyhydroxy, polyether, and polyhydroxy ether groupsand the like. Compounds having one or more of the foregoing groups aresuch compounds as: N-(3'-amino benzene sulfonyl) metanilic acid;N-(3-methyl amino benzene sulfonyl) suli'anilic acid; 2-(5'-- aminonaphthalene sulfonyl-i) amino naphthalene 6,8-disulfonic acid; 4"-aminobenzyl 3'- amino benzanilide; N-amino benzyl benzene sulfanilide;metanilic acid 4'-sulfo phenyl ester; 4-(4-aminobenzoyl) amino phenolpoly lycol ether; 3-(3-amino benzene sulfamino) benzene sulfamide;a-(3'-amino 4-methyl benzene sultamino) phthalic acid); 3"-amino benzenesulfonyl 3'-amino benzene sulfonyl sulfanilic acid;

amine, alkylated cycloheiiyl amine, benzyl amine,

' phenol, alkyl phenols, alkyl mercaptans, thio caustic soda, sulfuralkalies 'and the like.

phenols, nuclear halogenated or nuclear alkylated thio phenols and thelike. These compounds may also contain water-solubilizing groups suchas, for instance, groups from polybasic inorganic and organic acidsforming acid salts, quaternary ammonium groups, polyhydroxy, polyetheror polyhydroxy ether groups, and the like. For instance, 'taurine,glycocoll, sulfanilic acid, thioglycollic acid, m-amino phenyl trimethylammonium chloride, glucamine, p-amino phenol polyglycol ether, and thelike provide these desirable watersolubilizing groups.

When the radicals RR'N-, RS- and R0- to be substituted for remaininghalogen atoms have R and 3' representing hydrogen instead of hydrocarbongroups, such radicals may be introduced through the aid of any one of anumber of alkaline re'agentsthereby introducing hydroxy, amino ormercapto groups. These alkaline agents include ammonia, sodiumcarbonate,

Bleactions involving these alkaline reagents often produce especiallyvaluable reaction products when the heterocyclic compounds contain asmany as N-benzene sulfonyl benzidine; 2-amino 4-benzamino diphenyl;5-amino 6- (p-toluol sulfamino) naphthalene sulfonic acid-2; l-(3'-amino benzen'e sulfamino) benzene 3-trimethyl ammonium chloride, andothers.

As hereinbeiore stated, it is desirable in some instances to introducethe aromatic amino or mercapto compounds having one or more acid amidegroups in steps rather than as a preformed unit. In this stepwiseintroduction it is usually preferable to admit in succeeding steps thosecompounds that are normally produced or obtainable on splitting thearomatic amino compounds or the mercapto compounds of the typedescribed. For instance, the halogen containing heterocyclic compoundsmay be condensed first with compounds which contain besides areactivehydrogen atom one or more amino, sulfonic acid or carboxyl groups, or,such compounds may be used which contain groups readily convertible intothese groups such as nitro groups, acyl amino groups and the like. Whentheamino, sulfo or corboxyl group are not present themselves they may beintroduced by converting the nitro or acyl amino groups and the likewhich are present the purpose of tanning hides.

be used as precipitates for basic dyes in patent into such groups afterthe initial condensation has taken place. Likewise, water-solubilizinggroups may be introduced after the original condensation by subsequentsulfonation, or by subsequent introduction of quaternary ammonium I oralkyleneoxide groups.

Depending upon the results to be obtained, it is sometimes desirable toreplace all of the halogen atoms of the heterocyclic compounds witharomatic amino or aromatic mercapto compounds. For the production ofproducts .for use in certain other fields, it often is advantageous toreplace only a part of the halogen atoms with these compounds. Underthese latter circumstances it is usually preferable to replacetheremaining halogen atoms of the heterocyclic compounds with othergroups such as RR'N-,, 38-, or 1110-, in which R and R are hydrogen ordesirable hydrocarbon groups. When compounds containing such groups asRR'N, RS, or R0- have R and R representing-desirable hydrocarbon groups,they include such compounds as: alkyl amines, aniline, toluidine,cyclohexyl three replaceable halogen atoms.

It should be understood that the processe of the present inventionarenot to be confused with the processes whereby amino compounds having oneNHCO group and one or more groups capable of forming azo dyes arecondensed with cyanuric chloride and further condensed to produce azodyes. In the processes of the'present invention, the raw materials andthe ultimate products are different from those of the prior processesand are not suited for the production of azo dyes.

The compounds of the present invention are readily soluble in water,forming colloidal, aqueous solutions. They may be used exclusively or incombination with other tanning agents for They may also leather dyeingor for protection of animal fibers in substantive dye operations. Manyof the compounds also have surprising eflective insecticidalqualitiesand, therefore, find utility in the preparation of various insecticides.For instance, when they are applied to fibers of various sorts they actas a protection against moths.

The following examples, imwhich the quantities are expressed inparts byweight, will serve to illustrate the processes of the present invention,the products resulting therefrom and the utilities of such products.

' Example 1 One hundredand eighty five parts of cyanuric chloride'arebrought into a finely divided susperature is allowed to rise graduallyto 50 C.

The cyanuric chloride dissolves very rapidly producing a solution,strongly acid to congo paper, to which 300 parts of crystalline sodiumacetate is added. The solution, which is now neutral to congo paper, isallowedto stand for one to two hours. After this time, unchanged aminophenyl sulfonyl sulianilic acid should not be present at all or only intraces. Now parts 2,306,489 oi aniline and-150 parts of crystallinesodium I acetate are added and the mass heated to 90 to 100 C. andstirred at this temperature for. about one to two hours until anilineceases to be absorbed into the heterocyclic molecule. -The solution isthen neutralized with caustic soda and thereafter sodium carbonate isadded until there is a distinct alkaline reaction to litmus,

' of the condensation product will be precipitated out in an easilyfilterable form. The condensation product has the following structuralformula:

After drying at a temperature of 100 C., it forms an amorphouslight-grey yellowish powder which is easily soluble in water. Theaqueous solution fiuoresces neither in ordinary nor ultra-violet light.Upon cooling, a hot concentrated solution of the compound separates outin the form of a stiff, unfllterable gel. t

In the process, of this example, if after the exchange 01' the first twochlorine atoms of the cyanuric chloride by two groups from the aminobenzene sulfonyl sulfanilic acid, the third chlorine atom is replaced byreacting with sodium bicarbonate instead of adding aniline and moresodium acetate, and the solution is then heated to boiling and enoughcaustic'soda added to make the hot solution weakly alkaline tophenolphthalein, a product which contains a hydroxyl group instead ofthe aniline group will be obtained from the solution after it has stoodfor half an hour. Compare the above formula with an OH group replacingthe NH-C6H5 group. This product is considerably more soluble than thatobtained in the first reaction and cannot be precipitated from itsaqueous solution quantitatively with sodium chloride. When this prodnotis used as a tanning agent, it is advisable to bring about the desiredpH value after cooling the'solution by adding a suitable acid andthen'using the solution directly.

Example 2 One hundred and eighty five parts of eyanuric chloride aresuspended, as in the preceding example, in 5000 'parts of ice water. Aconcentrated aqueous solution of 1366 parts of the sodium salt of the4-[3'-(amino benzyl amino) following formula:

f is added during a period of half an houigat room C-NH-CsHi benzenesulfamino] benzene sulfonic acid of the mg g are no longer traceable.The resultins condensation product can be obtained in a solid form bysalting out-as in Example 1. On the other hand, the resulting solutionmay .be used directly for tanning purposes provided the solution isfirst adjusted to a suitable pH value."

. Example 3 Two hundred andeight parts of 4-methyl 2.6- dichlor 5-nitropyrimidine are dissolved by mildly heating in the minimal quantity ofacetone and the solution is poured into 5000 parts of ice water. To thesuspension obtained a concentrated aqueous solution of 1100 partsof thedi-sodiumsalt of the 1-(5' amino naphthalene sulionyl 1) aminonaphthalene 3,6-di-sulfonic acid of the -following formula:

' some SOsNB the condensation product salted out or it may be somodified as to be suitable for direct use in tanning.

- I Example 4 A concentrated solution of 185 parts or cyanuric chloridein acetone or alcohol is poured, while being stirred vigorously, into5000 parts of ice water. One hundred and forty parts of N-methyl taurineare added. under continued stirring until a clear solution is obtained.Then the solution is carefully neutralized with sodium bicarbonate and asolution of 322 parts of 2-,

hydroxy 3-methyl 5-(3'-a.mino benzol sulfonyl amino) benzoic acid and 40parts of sodium hydroxide in 5000 parts of water are added. Theresulting solution is stirred for an hour at room temperature, and thenheated slowly to C. while carefully adding sodium bicarbonate to keepthe reaction solution only slightly acid to ,litmus.

I On thecompletion of the conversion at a'temperature or 90C., 2000parts of sodium chloride are added and the solution is allowed to coolwhile being stirred. The resulting precipitate is filtered and dried.

An equivalent molecular quantity of 2,4-dichlorqllinazoline may be usedadvantageously in place of the cyanuric chloride.

Example 5 of partsof cyanuric chloride in 5000 parts of ice water,prepared as in Example 1, and after the suspension has been transformedinto a solution at a temperature of 20 C., a solution of 403.5 parts of3-(3'-amino benzene sulfamino) benzene sulfanilide, containing a minimalamount of diluted caustic soda for neutralization, is added undervigorous stirring. Stirring is continued at a temperature of 50 C.,while maintaining a slightly acid reaction to litmus by carefully addingsodium bicarbonate, until traces of tree amino compounds are no longerpresent; then 159 parts or the sodium salt of dry m-amino benzoic acidare introduced and the temperature is gradually raised to 90 C. Thereaction solution is kept slightly acid to litmus and the stirring iscontinued until the conversion is completed. Finally sodium carbonate isadded until the solution is slightly alkaline; then the condensationproduct is salted out, filtered and dried.

Example 6 A concentrated aqueous solution of 225 parts of disodium saltof the 'i-amino phthalic acid are added to a finely divided suspensionof 185 parts of eyanuric chloride in 5000 parts 01' ice water, preparedin accordance with Example 1. and stirred until the amino phthalic acidgroup is bound to the heterocyclic radical. The temperature is allowedto rise to about 40 C. and an aqueous solution of 314 parts of thesodium salt of the 3-(3'-amino benzene sulfamino) benzoic acid is added.The reaction is kept slightly acid to litmus by adding sodiumbicarbonate, until the second phase of the condensation is completed.Then 200 parts of solution of ammonium hydroxide are added to thissolution and the temperature is raised within an hour to 90 C. wherestirring is continued .ior one to two hours. The condensation product issalted out, filtered and dried.

Example 7 One hundred and sixty five parts of 2- am?no 4,6-dichl'or1,3,5-triazine are converted into a finely divided suspension bydissolving in a minimal amount of acetone or alcohol and stirring thesolution in 5000 parts of ice water. A-concentrated aqueous solution of200.5 parts of amino benzyl trimethyl ammonium chloride (obtained bynitrating benzyl chloride treating the mixture of the isomeric nitrobenzyl chlorides with trimethyl amine and reducing the nitro group withiron and a little acetic acid) is added to the foregoing suspensionwhereupon it very rapidly dissolves. Three hundred parts of crystallinesodium acetate are added then while stirring vigorously an alcoholicsolution of 150 parts of p-amino acetanilide are added slowly and thetemperature raised to 90 C. where heating is continued until the p-aminoacetanilide has disappeared. The condensation product is salted out andfiltered oil! when cold. The residue is then boiled with a 25% sulfuricacid solution until the acetyl group is split off. This solution isneutralized with slaked lime or calcium carbonate and filtered hot,thoroughly washing of! the gypsum with hot water. The filtrate isconcentrated and treated with 150 parts of calcium carbonate and asolution of 190 parts of p-toluol sulfo chloride in an equal quantity ofacetone is stirred in at a temperature of 20-25 C. The

solution is gradually heated to a temperature ofto C. and stirred untilthe sulfo chloride Example 8 One hundred and thirty nine parts ofm-nitro phenol are heated with 2000 parts or toluol and 5 parts orsodium ethylate in an autoclave to a temperature or C. and 880 partsoi-ethylene oxide are introduced under pressure at a temperature of 100'to C. The ethylene oxide is added gradually as the reaction p and thereaction conditions are maintained until a decrease in pressureindicates the completion of the reaction. Then the toluol is distilledoil and the residue reduced in an aqueous solution, in the customarymanner, with iron and a little acetic acid. The solution is madealkaline by adding sodium carbonate and freed irom iron by filtration.The solution, now containing a polyglyool ether of the m-amino phenol o!the general formula nm-cineo-(cmcm-mFcm-cm-on is made exactly neutral tolitmus by adding hydrochloric acid, then the solution in accordance withthe usual practice, is added at 5 6., to a finel divided suspension orparts of cyanuric chloride in"500o parts 0! water. the

cyanuric chloride is dissolved, a solution or 208 parts or metanilicacid 1-naphthalide in alcohol or acetone is added while raising thetemperature to 20 C.; then 300 parts of crystalline sodium acetate areadded and the suspension is' stirred at 45 C. until the naphthalide isdissolved. Finally 129 parts of n-octyl amine and 300 parts ofcrystalline sodium acetate are added and the solution stirred ata'temperature of 90 to 100 C. until the amine has disappeared. Thereaction product may be separated in the same manner as in the previousexamples.

Example 9 aqueous solution of 186 parts of the disodium salt of thebeta-mercapto ethane sulionic acid is added at a temperature not above+5 C. within a period of .one to two hours. After the conversion iscomplete, the solution is heated to 20' C. and an alcoholic solution of92 parts oi diphenyl-diamine are added in small quantities gradually,then 300 parts of crystalline sodium is converted. Then the excesscalcium carbonate is filtered of! while the solution is hot. Thecondensation product is salted out and filtered oflj when the solutionhas cooled. The condensation has the following structural formula:

. NH: 5 N/ \N acetate are added and the temperature is raised to 90C.where heating is continued until the diphenyl-diamine is bound to thetricyano mu cal. The reaction mixture is worked up in'the customarymanner by salting out, filtering and drying. I The structural formula oithe condensaworked up in the some manner as heretofore and tion protductobtainedis as follows: l

-o o-s-om-om-som.

ow- OT Example The condensation product of one mole of cyanuric chlorideand two 'moles of m'-amino benzene -sulifonyl sultanilic acid isprepared as in Example 1. Then 150 parts of m-amino'acetanillde'rand 300parts of crystalline sodium'aoetate are added and stirring continued ata temperature of 90' to 100 C. until the amino acetanilide hasdisappeared. The liquid is made distinctly alkaline by adding sodiumcarbonate and stirring is continued at a temperature of 90' to 100 C.until the alkaline reaction to litmus remains'for at least half an hourand until the diazotization value of the solution at least does notincrease. The solution is made slightly acid to litmus by carefullyadding hydrochloric acid and then it is cooled oil to room temperatureand phosgene has iollowing structural formula:

H0 EH N NH-$ -NK 4 9 Or tn OIN.

OaNa

. It should be understood that the present invention is not limited tothe specific processes, compounds, and compositions herein disclosed butthat it extends to all equivalentcompounds, compositions,'and processeswhich one skllled,in the art would consider within the scope of theappended claims.

' Example 12 1449 parts of metanilyle-metanilyle-sulianill acid of theformula HiN' . are dissolved msooo parts of water under mu ,tion of 120parts 01' sodium hydroxide; The solution is cooled down to +2 C.'and 185parts of finely powdered cyanuric chloride are given in.

, The mixture is stirred slowly increasing the temis introduced untila'test indicates that urea is no longer being ionned. The condensationproduct obtained is then isolated in the customary manner by saltingout,filtering and drying.

Example 11 A cold solution of 350 parts 01 the sodium salt of N-(m'-amino benzene sultonyl) sulfanilic acid in 1200 parts of water isadded to a finely divided suspension of 185 parts of cyanuric chloridein 5000 parts of ice water and stirred imtil the cyanuric chloride isdissolved. Then a concentrated aqueous solution 01 183 parts of thesodium salt of the N-(3',5'-diamino benzene su1- ionyl) sulranilic acidas well as 300 parts of crystalline sodium acetate is added and thetemperature allowed to rise to 45? C. where stirring is continued at atemperature of 45 to C. until free amino groups are no longer present.The solution is heated to boiling and sodium carbonate is added untilthe alkaline reaction remains even after lengthy boiling. The product isperature and is neutralized by slowly adding sodium bicarbonate andfinally sodium carbonate. The conversion is finished ii. the alkalinereaction remains stable during l-2 hours at a temperature of -95 C. Y vI g The thus formed clear brownish solution is cooled down at nearly 70C. and is acidified with concentrated hydrochloric acid until Congopaper is dyed blue.- The condensation product is precipitated by themineral acid in the form of a plastic resin. The condensation productsolidifies while cooling and may easily be powdered, filtered and dried.The reaction product is a redish-white powder easily soluble in water.

Example 13 At a finely divided and strongly stirred suspension of partsof cyanuric chloride in 5000 parts ice water a concentrated aqueoussolution 01 349 parts of the disodium salt of the N.N'-dimetanilyle-benzidine-2,2'-di-sulfonic acid of the formula mole soiNfl v11m m-mOOm-so NH:

- ture is carefully neutralised with sodium bicaris performed accordingto the process in Example 12.

Example 14 501 parts of p-acetaminothiophenol are dissolved in 2500parts of ethyl alcohol. The solutionris cooled down to +2 C. and asolution of 69 parts of sodium in 1500 parts of ethyl alcohol is added.Hereafter a solution 'of 185 parts of cyanuric chloride in 740 parts oftoluene is added and the mixture is stirred until the alkaline reactionis disappeared and the conversion is finished. Now 2000 parts of 38%hydrochloric acid is added and the mixture is heated under refluxuntil-the saponiflcation of the acetamino group is finished. One coolsdown, filters the precipidescribed tation and washes with water. Forforming thefree base the reaction product is treated with diluted sodalye,- is washed with water and dried.r

The base has the following formula:

450 parts of this base are suspended in 5000 parts of ethyl alcohol.

parts of benzoic acid-m-sulfochloride are added under good stirring. Themixture is warmed to 40 0., made alkaline by addition of sodiumcarbonate and finally heated under reflux. The reaction is finished assoon as the amino groups are disappeared. The alcohol is distilled off,not dissolved parts are filtered and the condensation product isprecipitated in the filtrate with hydrochloric acid. The precipitate isfiltered and dried. The thus obtained reaction product is a nearlycolourless powder which is easilysoluble in water in the presence ofsodium acetate or alkalies.

Example 15 To a finely divided suspension of 185 parts of cyanuricchloride in 5000 parts of ice water under vi orous stirring at 2-5{ asolution of 966 parts of metanilyle-metan lyle-sulfan iic acid and 80parts of sodium hydroxide in 2000 parts of water is added. The cyanuricchloride dissolves rapidly. Hereafter one neutral zes with sod um bcarbonate wh le slowly warm ng at 40 C. After the amino oups are disa ead an aqueous 'solut on' of 54 parts of m-p enylenediamine is add d. Nowat a temperatu e of 90 C. the formed ac d is neutral zed with sodi mcarbonate and finallv a week alkal ne reac ion is made.

.groups appropriately at least three sulfamide (SO2.NH)' groups in themolecule are of an excellent tanning action.

We claim:

1. A new compound composed of a tricyano group having linked to each-ofthe carbon atoms of the cyano group the radical derived frommetanilyle-metanilyle-sulfanilic acid, said radical being linked throughan amino nitrogen atom.

To the suspension 600 parts of crystallized sodium acetate and 662 2. Anew compound composed of two tricyano groups, a carbon atom ofonetricyano group 'being linked to a carbon atom of the other tricyanogroup through a m-phenyiene diamine radical, wherein the remainingcarbon atoms of the tricyano groups are substituted by the radicalderived from metanilyle-metanilyle-metanilic acid,

said radical being linked through an amino nitrogen atom.

3. A new tanning agent free of azo groups, a

compound consisting of a single azine nucleus containing from two tothree -c x) =N- groups as a part of the ring, wherein at least one X isselected from the group consisting of aminoandmercapto-aryl-sulfonamide-aryl radicals respectively connected to theazine ring through the amino nitrogen and mercapto sulfur atoms,

the aryl group containing not more than two ,rings; the'remaining X'sbeing selected from the group consisting of halogen,

S-R, and 0-H radicals, where the R's are selected from a member of thegroup consisting of consisting of (1) a single azine nucleus containingfrom two to three C(x) =N-- groups as part of the ring and -(2) a doubleazine nucleus, each azine ring of which contains onei group and from oneto two C(X)=N groups as part of the ring said azine rings being joinedthrough a polyamine radical the amino nitrogens of which are connectedto the carbon atoms of the 1 groups of the rings wherein at least one Xis selected from the group consisting of aminoandmercapto-aryl-sulfonamide-aryl radicals respectively connected to theazine ring through the amino nitrogen and mercapto sulfur atoms, thearyl group containing not more than two rings; the remaining X's beingselected from the group consisting of halogen,

. i I nl SR, and 0-H. radicals, where the R's are selected from a memberof the group consisting of hydrogen and hydrocarbon groups; saidcompound containing at least three sulfonamide linkages and at least onewater-solubilizing group in addition to the sulfonamide linkages.

5. A new tanning agent free of no groups. a compound consisting of asingle azine nucleus containing three'-C(X)=N groups as a part of thering, wherein each X is selected from the group consisting of aminoandmercapto-arylsulfonamide-aryl radicals respectively connected to theazine ring through the amino nitrogen and mercapto sulfur atoms, thearyl group being a benzene nucleus; said compound containing at leastthree sulfonamide linkages and at least one water-solubilizing group inaddition to the sulfonamide linkages,

linkages and at least one water-solubilising group 8. A new tanningagent tree of azo groups, a compound consisting of a single azinenucleus containing three --C(X)=N groups as part the ring wherein each Xis a mercapto-aryl-sulionamide-aryl-COOH radical connected to the azinering through the mercapto suiiuratom, the aryl group being a benzenenucleus.

7. A new tanning agent tree of am groups, a

' compound consisting of a single azine nucleus 8-3, and O-R radicals,where the R's are selected from a member of the group consisting ofhydrogen and hydrocarbon groups; said compound containing at least threesulronamide linkages and at least one water-solubilizing group inaddition to the sulfonamide linkages.

8. A new tanning agent free 01' azo groups, a compound consisting of adouble azine nucleus, each azine ring of which contains one group, andtwo -C(X)=N- groups as part or the ring, said azine rings being joinedthrough a diamine radical the .amino nitrogens of which are connected tothe carbon atoms of the groups of the rings wherein at least one x isselected from the group consisting of aminoandmercapto-aryl-sulfonamide-aryl radicals respectively connected to theazine ring through the amino nitrogen and mercapto sulfur atoms,

the aryl group containing not more than two rings; the remaining X'sbeing selected from the group consisting of halogen,

B-R, and O-R radicals, where the R's are selected from a member of thegroup consisting of hydrogen and hydrocarbon groups; said comin additionto thesulionamide linkages.

9. A new tanning agent free of azo groups, a compound consisting ofa-double azine nucleus,

' each azine ring oi 'which contains one group, and two C(X)=N groups aspart of the ring, said azine rings being joined t rough a diamineradical the amino nitrogens of which are connected to the carbon atomsof the groups of the rings wherein each x is selected from the groupconsisting of aminoand mercapto-aryl-sulfonamide-aryl radicalsrespectively connected to the azine ring through the amino nitrogen andmercapto sulfur atoms, the aryl group containing not more than tworings; said compound containing at least three sultonamide linkages andat least one .water-solubilizing group in addition to the suli'onamidelinkages.

10. A new tanning agent free of aao groups, a compound consisting of adouble azine nucleus, each azine ring of which contains one,

' group, and from one to two -c(x)=1sgroups pound containing at lea'stthree suiionamide as part of the ring, said azine rings being Joinedthrough an arylene-diamine radical the amino nitrogens of which areconnected to the carbon atoms of the groups of the rings wherein atleast one x is selected from the group consisting of aminoandmercapto-aryl-sultonamide-aryl radicals respectively connected to theazine ring through the amino nitrogen and mercapto sulfur atoms, thearyl group containing not more than two rings; the remaining X's beingselected from the group consisting of halogen,

8-3, and 0-H radicals, where the R's are selected from a member of thegroup consisting oi. hydrogen and hydrocarbon groups: said compoundcontaining at least three sulfonamide linkages and at least onewater-solubilizing group in addition to the sulionamide linkages.

ERIK SCHIRM.

